How to put two sourceanalyzers into one group?

I have created two classes and extends from sourceanalyzer. And also created two XML files with the same name as the analyzer. The value of ﻿SourceAnalyzer.Name and RuleGroup.Name attributes in XML files are same. I expect that all rules will be included
in same custom group. But I found two groups with same name on the settings form. Is there any solution for this?